tl;dr: put 1 point in vengefull spirit and go crazy with debuffs

Oh, defender. The tank with a magic wand usually crushes all your stereotypes. It's probably the best PvP tank there is.

Goodstuff:
Defender has an insane amount of control skills and debuffs, and it's practically pure pvp tank(you can use it in PvE, but I didn't like him as pve tank)

Allows you to heal yorself in critical moments.

, Blocks silence, sleep, stun-allows you to charge into enemies without fearing that you'll get controlled.

Good amount of hp and physical defense, has mages covered pretty well

+ fortification controls - stun and silence for 5 seconds(also, you generate more aggro for lol PvE lol)

very useful for control and it also generates agro. Use it and abuse it with AoE mages in party.

Necromancy Debuffs: and

Of course with 50% chance to have no cooldown

And as something to do while your controls are on CD

Cons:
-No good healing source(would you need it in PvP where you have a healer behind you?)
-No melee controls from Fight(yeah, the sword and board stereotypes)
-Hard to level up and PvE

Remaining skill point uses:
is probably the most obvious one. Debuffs casting speed,adds slow, and the only bad thing about it is channeling.
is a more defensive skill and some people really like it, so the option is there.
is pretty good for stopping enemies from running away. Also you can throw a guy off a cliff. Always fun.
could've been a great spell for group pvp against mages, but the 3m radius makes it not that good.

For mPvP, I'd actually switch with +. This build may just be able to survive to cast controls more times than a build without it.

Equipment:
Plate armor with +CON on it
Magic wand with +M.Atk and a shield
Necklace with +Max HP
Earrings with shield block/M.Def
Rings with M.Def